Thirded.
Mr. Clarke was an early pioneer of the science in fiction and thought some of his 'science' is now dated, he was fairly well on the mark.
Asimov was a ground-breaker and unbelievably prolific; his fiction's real worth is in the thoughts provoked, not so much the hard science.
Larry Niven's known space stories have much 'future science' that is so far ahead that we haven't yet proved or disproved the concepts... so they don't look corny to us. He's managed to not get too deep into the mundane 'consumer science' which changes so rapidly that nearly every other sci-fi story looks a tad silly science-wise after no more than 10 or 15 years.
Niven is the best.
I believe you can get a fast FPGA with an 8051 core; program up some interface logic......but you'd probably be banging your head, even if you succeed. Hell, back in the turbo XT days some guys built an 8086 compatible processor out of ECL discretes and bit-slice processors that ran at 100 MHz. But why?
$ Ka-Ching $
I just donated $5. I believe this is software worth supporting. It might just be one of the rare cases where "good tech" can squeeze 'tween the cracks in the wall of "big clout". Sure hope so.
It's nothing new, just a practical demonstration of what every system admin involved with their network's security ought to already have in mind.
The big guys (most of them, anyway) already deal with this. As a sometimes contractor to Deere and Co. (of the green tractor fame), I know that you can't get outside from their network on any port without going through (and authorizing with) a proxy. The same or similar is true at Caterpillar and a few others I've seen that you might know recognize.
So, it's nothing new, but a good demonstration and reminder.
It is now illegal for a amateur to transmit on that frequency to that satellite as the frequency has been reassigned to other uses (not Amateur Radio).
Hey, if you want science articles, go to the bloody science section like I do. Being off the front page, the SNR (Signal to Noise Ratio) is much better, the trolls don't all jump in and far fewer mod points are blown on silliness. The comments attached to this front-page article will consist of a great deal more fluff and lame attempts at humor.
But then again, maybe it's just a slow news day at/.
Drat. Google (or the satellite tracking community) has let me down. I can't find any current Keplerian elements (orbital data) on AO-7. Surely it is still kept track of, even though it's not necessarily used.
Interesting to note that it is expected (and wasn't made clear in the original article) that OSCAR-7 is operating on the solar array only. Meaning that it shuts down when it's not in sunlight and may or may not reboot each sunlight period. I find that believable because I wouldn't expect a NiCd battery pack to last even half that number of years. Especially given the type of charging circuit that was probably used in those days. Nobody used the dV/dT fast/smart charge method way back when.
However, when taken in excessive quantities or when combined with alcohol, acetaminophen may cause death due to liver failure. In fact, an overdose of acetaminophen is one of the most common causes of liver failure, as well as the most common cause of drug-induced liver disease in the United States.
The best way to avoid a hangover? Don't drink too much.
Re:Further OT: A quicker & dirtier transmitter
on
Field Day 2002
·
· Score: 1
Say... Isn't that what Marconi did, so long ago?
Of course, he didn't have the FCC to hassle him about plopping his signal down across every band in sight.
Now, class. For your homework, I want you to build a n FCC compliant spark-gap transmitter that operates legally in the 2 cm band.
Slightly OT: A quick & dirty transmitter...
on
Field Day 2002
·
· Score: 2, Interesting
I just setup a quick and dirty AM broadcast band radio transmitter yesterday... cheap and easy to do, if you've already got a fairly fancy function generator on-hand.
Equip: 1 BK Precision 4040A Function Generator 2 line, or higher, level audio source.
a Connect audio source to the VGC/Mod input b Set Int/Ext modulation selector to Ext (external) c Set AM/FM modulation selector to AM d Adjust the output frequency (the 'carrier') to something in the AM broadcast band (about 540 to 1150 KHz) e Attach a length of wire to the center lead of the Output BNC connector and crank the 'Output Level' adjustment to max. f Tune in on an AM reciever (you've got one of those, right?) g Jam on!
Actually, you could also do FM, but my FG (the 4040A) only goes to 20 MHz, way below the FM broadcast band of 88 to 108 MHz. Also, this isn't exactly a jammin' pirate station; let's just say I could pick it up from across the room.
Slashdot Mirror
Thirded. Mr. Clarke was an early pioneer of the science in fiction and thought some of his 'science' is now dated, he was fairly well on the mark. Asimov was a ground-breaker and unbelievably prolific; his fiction's real worth is in the thoughts provoked, not so much the hard science. Larry Niven's known space stories have much 'future science' that is so far ahead that we haven't yet proved or disproved the concepts... so they don't look corny to us. He's managed to not get too deep into the mundane 'consumer science' which changes so rapidly that nearly every other sci-fi story looks a tad silly science-wise after no more than 10 or 15 years. Niven is the best.
I believe you can get a fast FPGA with an 8051 core; program up some interface logic... ...but you'd probably be banging your head, even if you succeed. Hell, back in the turbo XT days some guys built an 8086 compatible processor out of ECL discretes and bit-slice processors that ran at 100 MHz. But why?
$ Ka-Ching $ I just donated $5. I believe this is software worth supporting. It might just be one of the rare cases where "good tech" can squeeze 'tween the cracks in the wall of "big clout". Sure hope so.
It's nothing new, just a practical demonstration of what every system admin involved with their network's security ought to already have in mind. The big guys (most of them, anyway) already deal with this. As a sometimes contractor to Deere and Co. (of the green tractor fame), I know that you can't get outside from their network on any port without going through (and authorizing with) a proxy. The same or similar is true at Caterpillar and a few others I've seen that you might know recognize. So, it's nothing new, but a good demonstration and reminder.
It orbits Earth a little over 20 times per 24 hour period. Yep. Its orbit is low and fast.
umm, a clarification is in order.
It is now illegal for a amateur to transmit on that frequency to that satellite as the frequency has been reassigned to other uses (not Amateur Radio).
Here are the NASA 2-line Keplerian elements for AO-7:
AO-07
1 07530U 74089B 02167.52996888 -.00000029 00000-0 10000-3 0 935
2 07530 101.7955 212.2077 0012102 193.4285 166.6467 12.53558681262239
Also, you may see it's orbit here
OK, Let's moderate Hemos' article (-1 Redundant)
/.
Hey, if you want science articles, go to the bloody science section like I do. Being off the front page, the SNR (Signal to Noise Ratio) is much better, the trolls don't all jump in and far fewer mod points are blown on silliness. The comments attached to this front-page article will consist of a great deal more fluff and lame attempts at humor.
But then again, maybe it's just a slow news day at
You mean like (reported yesterday)? Come on. Just 1 day, the repeat the story? That's gotta be a record.
Arg.
Should have checked the front page at www.amsat.org
Here are the keps for AO-7 if anyone else cares...
AO-07
1 07530U 74089B 02167.52996888 -.00000029 00000-0 10000-3 0 935
2 07530 101.7955 212.2077 0012102 193.4285 166.6467 12.53558681262239
Drat. Google (or the satellite tracking community) has let me down. I can't find any current Keplerian elements (orbital data) on AO-7. Surely it is still kept track of, even though it's not necessarily used.
Anyone know where to find the Keps?
More AO-7 status info here
Interesting to note that it is expected (and wasn't made clear in the original article) that OSCAR-7 is operating on the solar array only. Meaning that it shuts down when it's not in sunlight and may or may not reboot each sunlight period. I find that believable because I wouldn't expect a NiCd battery pack to last even half that number of years. Especially given the type of charging circuit that was probably used in those days. Nobody used the dV/dT fast/smart charge method way back when.
Go easy on that Tylenol. It can be mean to your liver, esp. when drinking.
Here is an excerpt from this URL:
However, when taken in excessive quantities or when combined with alcohol, acetaminophen may cause death due to liver failure. In fact, an overdose of acetaminophen is one of the most common causes of liver failure, as well as the most common cause of drug-induced liver disease in the United States.
The best way to avoid a hangover? Don't drink too much.
Say... Isn't that what Marconi did, so long ago? Of course, he didn't have the FCC to hassle him about plopping his signal down across every band in sight. Now, class. For your homework, I want you to build a n FCC compliant spark-gap transmitter that operates legally in the 2 cm band.
I just setup a quick and dirty AM broadcast band radio transmitter yesterday... cheap and easy to do, if you've already got a fairly fancy function generator on-hand.
Equip:
1 BK Precision 4040A Function Generator
2 line, or higher, level audio source.
a Connect audio source to the VGC/Mod input
b Set Int/Ext modulation selector to Ext (external)
c Set AM/FM modulation selector to AM
d Adjust the output frequency (the 'carrier') to something in the AM broadcast band (about 540 to 1150 KHz)
e Attach a length of wire to the center lead of the Output BNC connector and crank the 'Output Level' adjustment to max.
f Tune in on an AM reciever (you've got one of those, right?)
g Jam on!
Actually, you could also do FM, but my FG (the 4040A) only goes to 20 MHz, way below the FM broadcast band of 88 to 108 MHz. Also, this isn't exactly a jammin' pirate station; let's just say I could pick it up from across the room.
If the simulation is true to life, all you have to do is wait a few billion years and the pot & Floyd will pop right up on your screen.